Well the Bosmeri and Khaajiti are actually very closely related. Their skill sets are very similar ingame as well and both are well disposed to thief/roguelike classes, though bosmeri are notoriously better archers. The creation myths revolving around the the Khaajit and Bosmer races claim that they were born of the same litter and placed in the same lands, but an altercation ensued between the gods, forcing them to live in the arid, barren desert, or the harsh, poisonous jungles.
One story exists in the lore that explains how the Bosmer became created or came to be: The Words of Clan Mother Ahnissi. It goes as follows, in scripture from The Words Of Mother Ahnissi: 'Y'ffre heard the First Secret and snuck in behind Azura. And Y'ffre could not appreciate secrets, and he told Nirni of Azura's trick. So Nirni made the deserts hot and the sands biting. And Nirni made the forests wet and filled with poisons. And Nirni thanked Y'ffre and let him change the forest people also. And Y'ffre did not have Azura's subtle wisdom, so Y'ffre made the forest people elves always and never beasts. And Y'ffre named them Bosmer. And from that moment they were no longer in the same litter as the Khajiit.
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Lol yeah, I always exaggerate the feats of my characters in their backstories. If you're worried that I'll attempt to write like that, you have nothing to fear. Even the four consecutive shots to the eyes were a bit much. I kinda just push the envelope there because it won't affect gameplay as it would if I were to start shooting and beheading everyone I encounter ingame. However, I do realize it can be a problem, so I went ahead and redid the end a bit.